Spring Cloud AWS: Missing SNS message signature verification allows spoofing of HTTP/HTTPS endpoint notifications

Spring Cloud AWS simplifies using AWS managed services in a Spring and Spring Boot applications. From 3.0.0 to 4.0.1, pplications using Spring Cloud AWS SNS HTTP/HTTPS endpoint support (@NotificationMessageMapping, @NotificationSubscriptionMapping, @NotificationUnsubscribeConfirmationMapping) did not verify the signature of incoming SNS messages. An unauthenticated attacker who knows the endpoint URL could send crafted HTTP POST requests mimicking SNS Notification or SubscriptionConfirmation messages. This vulnerability is fixed in 4.0.2.